From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B437E161 for ; Sun, 16 Jul 2023 01:09:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C3452C433C7; Sun, 16 Jul 2023 01:09:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689469772; bh=5SSm4qEXPJuLohs5+byCGS3o4lRGePIKkaLKy1/+IXc=; h=From:To:Cc:Subject:Date:From; b=RNE0S0KQf9cRwje4zpnYyVSB45dXyxazFqRNu79k0NvYqvDcqN3SDgAQKkSSlThfu bvt8zjM+7qrgXnrITpz0BXGwD6EIWrjEvP8Sgouy+zj3Ti9+08V0ssNOZS4t84SVjB +i7dELXzNCAV4Ps/cElbr5vod97Fi8CSEMEzQsKkGpjCI4AAnTvKvmFtgbTxa0igmt jaz3LqNmLDx1Uirxipq9HaXZTwq2bhq0XjBjmWxL89463OKLVZYI9/hm0sA1muGdRd sBVyyfPI2Yan0+hwlQsdkB2X/Vo7PgdhJx7e4N8Sl0NgCz4jmCBnYdCKiKthemyOTr QSYdaRb4YsDzw== From: Chao Yu To: sj@kernel.org, akpm@linux-foundation.org, damon@lists.linux.dev Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Chao Yu Subject: [PATCH 1/2] mm/damon/dbgfs: reduce stack usage in str_to_schemes() Date: Sun, 16 Jul 2023 09:09:26 +0800 Message-Id: <20230716010927.3010606-1-chao@kernel.org> X-Mailer: git-send-email 2.40.1 Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit struct damos_quota quota caused the stack usage of str_to_schemes() to grow beyond the warning limit on 32-bit architectures w/ gcc. mm/damon/dbgfs.c: In function ‘str_to_schemes’: mm/damon/dbgfs.c:292:1: warning: the frame size of 1496 bytes is larger than 1024 bytes [-Wframe-larger-than=] Allocating dynamic memory in str_to_schemes() to fix this issue. Signed-off-by: Chao Yu --- mm/damon/dbgfs.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/mm/damon/dbgfs.c b/mm/damon/dbgfs.c index 124f0f8c97b7..78acc7366895 100644 --- a/mm/damon/dbgfs.c +++ b/mm/damon/dbgfs.c @@ -237,18 +237,26 @@ static struct damos **str_to_schemes(const char *str, ssize_t len, int pos = 0, parsed, ret; unsigned int action_input; enum damos_action action; + struct damos_quota *quota; schemes = kmalloc_array(max_nr_schemes, sizeof(scheme), GFP_KERNEL); if (!schemes) return NULL; + quota = kmalloc(sizeof(struct damos_quota), GFP_KERNEL); + if (!quota) { + kfree(schemes); + return NULL; + } + *nr_schemes = 0; while (pos < len && *nr_schemes < max_nr_schemes) { struct damos_access_pattern pattern = {}; - struct damos_quota quota = {}; struct damos_watermarks wmarks; + memset(quota, 0, sizeof(struct damos_quota)); + ret = sscanf(&str[pos], "%lu %lu %u %u %u %u %u %lu %lu %lu %u %u %u %u %lu %lu %lu %lu%n", &pattern.min_sz_region, &pattern.max_sz_region, @@ -256,10 +264,10 @@ static struct damos **str_to_schemes(const char *str, ssize_t len, &pattern.max_nr_accesses, &pattern.min_age_region, &pattern.max_age_region, - &action_input, "a.ms, - "a.sz, "a.reset_interval, - "a.weight_sz, "a.weight_nr_accesses, - "a.weight_age, &wmarks.metric, + &action_input, "a->ms, + "a->sz, "a->reset_interval, + "a->weight_sz, "a->weight_nr_accesses, + "a->weight_age, &wmarks.metric, &wmarks.interval, &wmarks.high, &wmarks.mid, &wmarks.low, &parsed); if (ret != 18) @@ -278,15 +286,17 @@ static struct damos **str_to_schemes(const char *str, ssize_t len, goto fail; pos += parsed; - scheme = damon_new_scheme(&pattern, action, "a, &wmarks); + scheme = damon_new_scheme(&pattern, action, quota, &wmarks); if (!scheme) goto fail; schemes[*nr_schemes] = scheme; *nr_schemes += 1; } + kfree(quota); return schemes; fail: + kfree(quota); free_schemes_arr(schemes, *nr_schemes); return NULL; } -- 2.40.1